1. Field of the Invention
The present invention relates to an etching device for semiconductor wafers or the like and more specifically to an etching device which greatly simplifies the etching process while providing more uniform and improved quality.
2. Description of the Prior Art
FIG. 1 shows an etching arrangement disclosed in an article entitled A SILICON DIAPHRAGM FORMATION FOR PRESSURE SENSOR BY ANODIC OXIDATION ETCH - STOP by M. Hirata disclosed in the 1985 IEEE colloquium compilation page 287.
With this arrangement in order to electrochemically etch portions of a semiconductor wafer 1 it has been necessary to execute a number of preparatory steps including (by way of example) preparing suitable temporary electrodes on the surface of each wafer prior to the actual etching process and removing the same thereafter.
Further, it has also been necessary to individually connect each of the wafers to a source of electromotive force 2 in a manner such as shown in FIG. 1 in order to actually conduct the etching process. In the instance it is desired to simultaneously etch a number of wafers, as the shape and location of the cathode 3 from the work pieces has a marked effect on the process, extreme care must be exercised when arranging the cathode 3 and the wafers 1 with respect to the same. However, due to the inevitably minute differences in distance and shape which occur despite the most careful efforts to avoid the same, a variation in the quality of the finished articles has thus far proven inevitable.